<?php  if (!defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package        CodeIgniter
 * @author        ExpressionEngine Dev Team
 * @copyright   Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license        http://codeigniter.com/user_guide/license.html
 * @link        http://codeigniter.com
 * @since        Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * oci8 Database Adapter Class
 *
 * Note: _DB is an extender class that the app controller
 * creates dynamically based on whether the active record
 * class is being used or not.
 *
 * @package        CodeIgniter
 * @subpackage  Drivers
 * @category    Database
 * @author        ExpressionEngine Dev Team
 * @link        http://codeigniter.com/user_guide/database/
 */

/**
 * oci8 Database Adapter Class
 *
 * This is a modification of the DB_driver class to
 * permit access to oracle databases
 *
 * @author      Kelly McArdle
 *
 */

class CI_DB_oci8_driver extends CI_DB
{

    var $dbdriver = 'oci8';

    // The character used for excaping
    var $_escape_char = '"';

    // clause and character used for LIKE escape sequences
    var $_like_escape_str = " escape '%s' ";
    var $_like_escape_chr = '!';

    /**
     * The syntax to count rows is slightly different across different
     * database engines, so this string appears in each driver and is
     * used for the count_all() and count_all_results() functions.
     */
    var $_count_string = "SELECT COUNT(1) AS ";
    var $_random_keyword = ' ASC'; // not currently supported

    // Set "auto commit" by default
    var $_commit = OCI_COMMIT_ON_SUCCESS;

    // need to track statement id and cursor id
    var $stmt_id;
    var $curs_id;

    // if we use a limit, we will add a field that will
    // throw off num_fields later
    var $limit_used;

    /**
     * Non-persistent database connection
     *
     * @access  private called by the base class
     * @return  resource
     */
    public function db_connect()
    {
        return @oci_connect($this->username, $this->password, $this->hostname, $this->char_set);
    }

    // --------------------------------------------------------------------

    /**
     * Persistent database connection
     *
     * @access  private called by the base class
     * @return  resource
     */
    public function db_pconnect()
    {
        return @oci_pconnect($this->username, $this->password, $this->hostname, $this->char_set);
    }

    // --------------------------------------------------------------------

    /**
     * Reconnect
     *
     * Keep / reestablish the db connection if no queries have been
     * sent for a length of time exceeding the server's idle timeout
     *
     * @access    public
     * @return    void
     */
    public function reconnect()
    {
        // not implemented in oracle
        return;
    }

    // --------------------------------------------------------------------

    /**
     * Select the database
     *
     * @access  private called by the base class
     * @return  resource
     */
    public function db_select()
    {
        // Not in Oracle - schemas are actually usernames
        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Set client character set
     *
     * @access    public
     * @param    string
     * @param    string
     * @return    resource
     */
    public function db_set_charset($charset, $collation)
    {
        // @todo - add support if needed
        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Version number query string
     *
     * @access  protected
     * @return  string
     */
    protected function _version()
    {
        return oci_server_version($this->conn_id);
    }

    // --------------------------------------------------------------------

    /**
     * Execute the query
     *
     * @access  protected  called by the base class
     * @param   string  an SQL query
     * @return  resource
     */
    protected function _execute($sql)
    {
        // oracle must parse the query before it is run. All of the actions with
        // the query are based on the statement id returned by ociparse
        $this->stmt_id = FALSE;
        $this->_set_stmt_id($sql);
        oci_set_prefetch($this->stmt_id, 1000);
        return @oci_execute($this->stmt_id, $this->_commit);
    }

    /**
     * Generate a statement ID
     *
     * @access  private
     * @param   string  an SQL query
     * @return  none
     */
    private function _set_stmt_id($sql)
    {
        if (!is_resource($this->stmt_id)) {
            $this->stmt_id = oci_parse($this->conn_id, $this->_prep_query($sql));
        }
    }

    // --------------------------------------------------------------------

    /**
     * Prep the query
     *
     * If needed, each database adapter can prep the query string
     *
     * @access  private called by execute()
     * @param   string  an SQL query
     * @return  string
     */
    private function _prep_query($sql)
    {
        return $sql;
    }

    // --------------------------------------------------------------------

    /**
     * getCursor.  Returns a cursor from the datbase
     *
     * @access  public
     * @return  cursor id
     */
    public function get_cursor()
    {
        $this->curs_id = oci_new_cursor($this->conn_id);
        return $this->curs_id;
    }

    // --------------------------------------------------------------------

    /**
     * Stored Procedure.  Executes a stored procedure
     *
     * @access  public
     * @param   package     package stored procedure is in
     * @param   procedure   stored procedure to execute
     * @param   params      array of parameters
     * @return  array
     *
     * params array keys
     *
     * KEY      OPTIONAL    NOTES
     * name        no        the name of the parameter should be in :<param_name> format
     * value    no        the value of the parameter.  If this is an OUT or IN OUT parameter,
     *                    this should be a reference to a variable
     * type        yes        the type of the parameter
     * length    yes        the max size of the parameter
     */
    public function stored_procedure($package, $procedure, $params)
    {
        if ($package == '' OR $procedure == '' OR !is_array($params)) {
            if ($this->db_debug) {
                log_message('error', 'Invalid query: ' . $package . '.' . $procedure);
                return $this->display_error('db_invalid_query');
            }
            return FALSE;
        }

        // build the query string
        $sql = "begin $package.$procedure(";

        $have_cursor = FALSE;
        foreach ($params as $param) {
            $sql .= $param['name'] . ",";

            if (array_key_exists('type', $param) && ($param['type'] === OCI_B_CURSOR)) {
                $have_cursor = TRUE;
            }
        }
        $sql = trim($sql, ",") . "); end;";

        $this->stmt_id = FALSE;
        $this->_set_stmt_id($sql);
        $this->_bind_params($params);
        $this->query($sql, FALSE, $have_cursor);
    }

    // --------------------------------------------------------------------

    /**
     * Bind parameters
     *
     * @access  private
     * @return  none
     */
    private function _bind_params($params)
    {
        if (!is_array($params) OR !is_resource($this->stmt_id)) {
            return;
        }

        foreach ($params as $param) {
            foreach (array('name', 'value', 'type', 'length') as $val) {
                if (!isset($param[$val])) {
                    $param[$val] = '';
                }
            }

            oci_bind_by_name($this->stmt_id, $param['name'], $param['value'], $param['length'], $param['type']);
        }
    }

    // --------------------------------------------------------------------

    /**
     * Begin Transaction
     *
     * @access    public
     * @return    bool
     */
    public function trans_begin($test_mode = FALSE)
    {
        if (!$this->trans_enabled) {
            return TRUE;
        }

        // When transactions are nested we only begin/commit/rollback the outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }

        // Reset the transaction failure flag.
        // If the $test_mode flag is set to TRUE transactions will be rolled back
        // even if the queries produce a successful result.
        $this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;

        $this->_commit = OCI_DEFAULT;
        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Commit Transaction
     *
     * @access    public
     * @return    bool
     */
    public function trans_commit()
    {
        if (!$this->trans_enabled) {
            return TRUE;
        }

        // When transactions are nested we only begin/commit/rollback the outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }

        $ret = oci_commit($this->conn_id);
        $this->_commit = OCI_COMMIT_ON_SUCCESS;
        return $ret;
    }

    // --------------------------------------------------------------------

    /**
     * Rollback Transaction
     *
     * @access    public
     * @return    bool
     */
    public function trans_rollback()
    {
        if (!$this->trans_enabled) {
            return TRUE;
        }

        // When transactions are nested we only begin/commit/rollback the outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }

        $ret = oci_rollback($this->conn_id);
        $this->_commit = OCI_COMMIT_ON_SUCCESS;
        return $ret;
    }

    // --------------------------------------------------------------------

    /**
     * Escape String
     *
     * @access  public
     * @param   string
     * @param    bool    whether or not the string will be used in a LIKE condition
     * @return  string
     */
    public function escape_str($str, $like = FALSE)
    {
        if (is_array($str)) {
            foreach ($str as $key => $val) {
                $str[$key] = $this->escape_str($val, $like);
            }

            return $str;
        }

        $str = remove_invisible_characters($str);

        // escape LIKE condition wildcards
        if ($like === TRUE) {
            $str = str_replace(array('%', '_', $this->_like_escape_chr),
                array($this->_like_escape_chr . '%', $this->_like_escape_chr . '_', $this->_like_escape_chr . $this->_like_escape_chr),
                $str);
        }

        return $str;
    }

    // --------------------------------------------------------------------

    /**
     * Affected Rows
     *
     * @access  public
     * @return  integer
     */
    public function affected_rows()
    {
        return @oci_num_rows($this->stmt_id);
    }

    // --------------------------------------------------------------------

    /**
     * Insert ID
     *
     * @access  public
     * @return  integer
     */
    public function insert_id()
    {
        // not supported in oracle
        return $this->display_error('db_unsupported_function');
    }

    // --------------------------------------------------------------------

    /**
     * "Count All" query
     *
     * Generates a platform-specific query string that counts all records in
     * the specified database
     *
     * @access  public
     * @param   string
     * @return  string
     */
    public function count_all($table = '')
    {
        if ($table == '') {
            return 0;
        }

        $query = $this->query($this->_count_string . $this->_protect_identifiers('numrows') . " FROM " . $this->_protect_identifiers($table, TRUE, NULL, FALSE));

        if ($query == FALSE) {
            return 0;
        }

        $row = $query->row();
        $this->_reset_select();
        return (int)$row->numrows;
    }

    // --------------------------------------------------------------------

    /**
     * Show table query
     *
     * Generates a platform-specific query string so that the table names can be fetched
     *
     * @access    protected
     * @param    boolean
     * @return    string
     */
    protected function _list_tables($prefix_limit = FALSE)
    {
        $sql = "SELECT TABLE_NAME FROM ALL_TABLES";

        if ($prefix_limit !== FALSE AND $this->dbprefix != '') {
            $sql .= " WHERE TABLE_NAME LIKE '" . $this->escape_like_str($this->dbprefix) . "%' " . sprintf($this->_like_escape_str, $this->_like_escape_chr);
        }

        return $sql;
    }

    // --------------------------------------------------------------------

    /**
     * Show column query
     *
     * Generates a platform-specific query string so that the column names can be fetched
     *
     * @access  protected
     * @param   string  the table name
     * @return  string
     */
    protected function _list_columns($table = '')
    {
        return "SELECT COLUMN_NAME FROM all_tab_columns WHERE table_name = '$table'";
    }

    // --------------------------------------------------------------------

    /**
     * Field data query
     *
     * Generates a platform-specific query so that the column data can be retrieved
     *
     * @access  public
     * @param   string  the table name
     * @return  object
     */
    protected function _field_data($table)
    {
        return "SELECT * FROM " . $table . " where rownum = 1";
    }

    // --------------------------------------------------------------------

    /**
     * The error message string
     *
     * @access  protected
     * @return  string
     */
    protected function _error_message()
    {
        // If the error was during connection, no conn_id should be passed
        $error = is_resource($this->conn_id) ? oci_error($this->conn_id) : oci_error();
        return $error['message'];
    }

    // --------------------------------------------------------------------

    /**
     * The error message number
     *
     * @access  protected
     * @return  integer
     */
    protected function _error_number()
    {
        // Same as _error_message()
        $error = is_resource($this->conn_id) ? oci_error($this->conn_id) : oci_error();
        return $error['code'];
    }

    // --------------------------------------------------------------------

    /**
     * Escape the SQL Identifiers
     *
     * This function escapes column and table names
     *
     * @access    protected
     * @param    string
     * @return    string
     */
    protected function _escape_identifiers($item)
    {
        if ($this->_escape_char == '') {
            return $item;
        }

        foreach ($this->_reserved_identifiers as $id) {
            if (strpos($item, '.' . $id) !== FALSE) {
                $str = $this->_escape_char . str_replace('.', $this->_escape_char . '.', $item);

                // remove duplicates if the user already included the escape
                return preg_replace('/[' . $this->_escape_char . ']+/', $this->_escape_char, $str);
            }
        }

        if (strpos($item, '.') !== FALSE) {
            $str = $this->_escape_char . str_replace('.', $this->_escape_char . '.' . $this->_escape_char, $item) . $this->_escape_char;
        } else {
            $str = $this->_escape_char . $item . $this->_escape_char;
        }

        // remove duplicates if the user already included the escape
        return preg_replace('/[' . $this->_escape_char . ']+/', $this->_escape_char, $str);
    }

    // --------------------------------------------------------------------

    /**
     * From Tables
     *
     * This function implicitly groups FROM tables so there is no confusion
     * about operator precedence in harmony with SQL standards
     *
     * @access    protected
     * @param    type
     * @return    type
     */
    protected function _from_tables($tables)
    {
        if (!is_array($tables)) {
            $tables = array($tables);
        }

        return implode(', ', $tables);
    }

    // --------------------------------------------------------------------

    /**
     * Insert statement
     *
     * Generates a platform-specific insert string from the supplied data
     *
     * @access  public
     * @param   string  the table name
     * @param   array   the insert keys
     * @param   array   the insert values
     * @return  string
     */
    protected function _insert($table, $keys, $values)
    {
        return "INSERT INTO " . $table . " (" . implode(', ', $keys) . ") VALUES (" . implode(', ', $values) . ")";
    }

    // --------------------------------------------------------------------

    /**
     * Insert_batch statement
     *
     * Generates a platform-specific insert string from the supplied data
     *
     * @access      protected
     * @param       string  the table name
     * @param       array   the insert keys
     * @param       array   the insert values
     * @return      string
     */
    protected function _insert_batch($table, $keys, $values)
    {
        $keys = implode(', ', $keys);
        $sql = "INSERT ALL\n";

        for ($i = 0, $c = count($values); $i < $c; $i++) {
            $sql .= '	INTO ' . $table . ' (' . $keys . ') VALUES ' . $values[$i] . "\n";
        }

        $sql .= 'SELECT * FROM dual';

        return $sql;
    }

    // --------------------------------------------------------------------

    /**
     * Update statement
     *
     * Generates a platform-specific update string from the supplied data
     *
     * @access    protected
     * @param    string    the table name
     * @param    array    the update data
     * @param    array    the where clause
     * @param    array    the orderby clause
     * @param    array    the limit clause
     * @return    string
     */
    protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE)
    {
        foreach ($values as $key => $val) {
            $valstr[] = $key . " = " . $val;
        }

        $limit = (!$limit) ? '' : ' LIMIT ' . $limit;

        $orderby = (count($orderby) >= 1) ? ' ORDER BY ' . implode(", ", $orderby) : '';

        $sql = "UPDATE " . $table . " SET " . implode(', ', $valstr);

        $sql .= ($where != '' AND count($where) >= 1) ? " WHERE " . implode(" ", $where) : '';

        $sql .= $orderby . $limit;

        return $sql;
    }

    // --------------------------------------------------------------------

    /**
     * Truncate statement
     *
     * Generates a platform-specific truncate string from the supplied data
     * If the database does not support the truncate() command
     * This function maps to "DELETE FROM table"
     *
     * @access    protected
     * @param    string    the table name
     * @return    string
     */
    protected function _truncate($table)
    {
        return "TRUNCATE TABLE " . $table;
    }

    // --------------------------------------------------------------------

    /**
     * Delete statement
     *
     * Generates a platform-specific delete string from the supplied data
     *
     * @access    protected
     * @param    string    the table name
     * @param    array    the where clause
     * @param    string    the limit clause
     * @return    string
     */
    protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
    {
        $conditions = '';

        if (count($where) > 0 OR count($like) > 0) {
            $conditions = "\nWHERE ";
            $conditions .= implode("\n", $this->ar_where);

            if (count($where) > 0 && count($like) > 0) {
                $conditions .= " AND ";
            }
            $conditions .= implode("\n", $like);
        }

        $limit = (!$limit) ? '' : ' LIMIT ' . $limit;

        return "DELETE FROM " . $table . $conditions . $limit;
    }

    // --------------------------------------------------------------------

    /**
     * Limit string
     *
     * Generates a platform-specific LIMIT clause
     *
     * @access  protected
     * @param   string  the sql query string
     * @param   integer the number of rows to limit the query to
     * @param   integer the offset value
     * @return  string
     */
    protected function _limit($sql, $limit, $offset)
    {
        $limit = $offset + $limit;
        $newsql = "SELECT * FROM (select inner_query.*, rownum rnum FROM ($sql) inner_query WHERE rownum < $limit)";

        if ($offset != 0) {
            $newsql .= " WHERE rnum >= $offset";
        }

        // remember that we used limits
        $this->limit_used = TRUE;

        return $newsql;
    }

    // --------------------------------------------------------------------

    /**
     * Close DB Connection
     *
     * @access  protected
     * @param   resource
     * @return  void
     */
    protected function _close($conn_id)
    {
        @oci_close($conn_id);
    }


}



/* End of file oci8_driver.php */
/* Location: ./system/database/drivers/oci8/oci8_driver.php */
